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PubMed2001

Visualization of nuclei in Aspergillus oryzae with EGFP and analysis of the number of nuclei in each conidium by FACS.

Aspergillus oryzae has been reported to form conidia with multinuclei. In order to analyze nuclei in living cells, we developed an expression system of the A. nidutans histone H2B protein tagged by EGFP (H2B::EGFP). In both A. oryzae niaD300 and A. nidulans FGSC89 transformants expressing H2B::EGFP, fluorescence was detected in nuclear regions of hyphae and conidia. While a conidium contained only one fluorescent spot in the A. nidulans transformant, approximately 66% of conidia had two, 24% had one, and 10% had three or more in the A. oryzae transformant. The conidia expressing H2B::EGFP were put through FACS (fluorescence-activated cell sorting) analysis and two sharp peaks, corresponding to one and two nuclei in each conidium, were noted in the A. oryzae transformant. In addition, the A. oryzae uninucleate conidia that were successfully isolated by FACS reproduced conidia with almost the same number distribution of nuclei as that of the original. Conidia of five A. oryzae strains used in sake brewing were scored for the number of nuclei, showing that a varied number of nuclei existed in each conidium and some strains had a small number of uninucleate conidia.

Alcoholic Beverages↗
PubMed1978

[Nuclei of the mammillary bodies and their fiber connections in cattle (Bos taurus var. domesticus). I. Nuclei of the mammillary bodies in cattle].

1. In the present neuroanatomic study the topography and cytoarchitectonic of the nuclei of the mamillary body of cattle are described and quantitative-morphologically investigated in 14 series of brains (6 frontal, 4 sagittal and 4 horizontal series, stained by the methods after Nissl, Klüver and Barrera and after Heidenhain). 2. The medial mamillary nucleus of cattle is with an average volume of 47.7 mm3 the largest nucleus of the mamillary body. It contains about 715,000 cells with a cell density of 15,000 cells/mm3 and can cytoarchitectonically be subdivided into a medial part and a lateral part. 3. The median mamillary nucleus is an unpaired and clearly defined nucleus which accounts with an average volume of 16.9 mm3 for a quarter of the whole volume of the nuclei belonging to the mamillary body, however with 11,000 cells/mm3 it shows a relatively small cell density in comparison with the other mamillary nuclei. 4. The lateral mamillary nuclei of cattle are situated in the rostral third of the mamillary body and account for 5.3 per cent of the whole volume of the nuclei. About 28,000 cells with a cell density of 15,000 cells/mm3 were found in each nucleus.

Animals↗
PubMed2001

Basic organization of projections from the oval and fusiform nuclei of the bed nuclei of the stria terminalis in adult rat brain.

The organization of axonal projections from the oval and fusiform nuclei of the bed nuclei of the stria terminalis (BST) was characterized with the Phaseolus vulgaris-leucoagglutinin (PHAL) anterograde tracing method in adult male rats. Within the BST, the oval nucleus (BSTov) projects very densely to the fusiform nucleus (BSTfu) and also innervates the caudal anterolateral area, anterodorsal area, rhomboid nucleus, and subcommissural zone. Outside the BST, its heaviest inputs are to the caudal substantia innominata and adjacent central amygdalar nucleus, retrorubral area, and lateral parabrachial nucleus. It generates moderate inputs to the caudal nucleus accumbens, parasubthalamic nucleus, and medial and ventrolateral divisions of the periaqueductal gray, and it sends a light input to the anterior parvicellular part of the hypothalamic paraventricular nucleus and nucleus of the solitary tract. The BSTfu displays a much more complex projection pattern. Within the BST, it densely innervates the anterodorsal area, dorsomedial nucleus, and caudal anterolateral area, and it moderately innervates the BSTov, subcommissural zone, and rhomboid nucleus. Outside the BST, the BSTfu provides dense inputs to the nucleus accumbens, caudal substantia innominata and central amygdalar nucleus, thalamic paraventricular nucleus, hypothalamic paraventricular and periventricular nuclei, hypothalamic dorsomedial nucleus, perifornical lateral hypothalamic area, and lateral tegmental nucleus. Moderately dense inputs are found in the parastrial, tuberal, dorsal raphé, and parabrachial nuclei and in the retrorubral area, ventrolateral division of the periaqueductal gray, and pontine central gray. Light projections end in the olfactory tubercle, lateral septal nucleus, posterior basolateral amygdalar nucleus, supramammillary nucleus, and nucleus of the solitary tract. These and other results suggest that the BSTov and BSTfu are basal telencephalic parts of a circuit that coordinates autonomic, neuroendocrine, and ingestive behavioral responses during stress.

Animals↗
PubMed1987

Development of the precerebellar nuclei in the rat: III. The posterior precerebellar extramural migratory stream and the lateral reticular and external cuneate nuclei.

Sequential thymidine radiograms from rats injected on day E15 and killed thereafter at daily intervals up to day E22 were analyzed to trace the migratory routes and settling patterns of neurons of the lateral reticular nucleus and the external cuneate nucleus. The neurons of the lateral reticular and external cuneate nuclei originate in the primary precerebellar neuroepithelium at the same site as the inferior olivary neurons but follow a different migratory route. The labeled young neurons that are produced on day E15 (the last one-third of the total) join the posterior precerebellar extramural migratory stream. The cells move circumferentially over the wall of the medulla in a ventral direction and by day E17 reach the midline and cross it beneath the inferior olive. The crossing cells apparently continue to migrate circumferentially on the opposite side. One complement of these cells begins to form a ventrolateral extramural condensation on day E19. By day E20 some cells begin to penetrate the parenchyma and settle as neurons of the lateral reticular nucleus. The settling of the lateral reticular neurons continues on the following day, and by day E22 all the cells destined for the lateral reticular nucleus have penetrated the parenchyma. A dorsomedial-to-ventrolateral neurogenetic gradient is indicated for the settling lateral reticular neurons. Another complement of migrating cells continues dorsally and forms a condensation on day E19 that we interpret as the external cuneate component of the crossed stream. These cells begin to penetrate the parenchyma on day E20, and by days E21 and E22 two components of the external cuneate nucleus are identifiable-the dorsal and ventral external cuneate nuclei. The neurons of the lateral reticular and external cuneate nuclei differ from neurons of all the other precerebellar nuclei in that their cerebellar projection is predominantly ipsilateral. We speculate that the axons of all precerebellar neurons are genetically specified to cross the midline ventrally to provide a contralateral efferent projection, but this is modified in the case of the ipsilaterally projecting lateral reticular and external cuneate neurons by the cell bodies following their neurites to the opposite side.

Animals↗
PubMed1986

Serotonin turnover in discrete hypothalamic nuclei and mesencephalic raphe nuclei of young and adult spontaneously hypertensive rats.

Serotonin levels and turnover were analyzed in discrete forebrain and mesencephalic nuclei of young (4-week-old) and adult (14-week-old) spontaneously hypertensive rats and age-matched normotensive control Wistar Kyoto rats. Most changes observed were age-dependent, and occurred only in young, early hypertensive rats. Both serotonin levels and the accumulation rate of 5-hydroxy-tryptophan after L-amino acid decarboxylase inhibition were higher in the nuclei periventricularis and paraventricularis of the hypothalamus of young hypertensive rats than in controls. In addition, 4-week-old spontaneously hypertensive rats showed higher 5-hydroxytryptophan accumulation rates in the nuclei supraopticus and dorsomedialis of the hypothalamus than controls. The only difference in serotonin metabolism found in adult hypertensive rats was high serotonin concentration in the median eminence of the hypertensive animals. Our results suggest the presence of anatomically specific, age-dependent alterations in serotonin metabolism, localized to selected hypothalamic nuclei in young hypertensive rats. These data support a role for the hypothalamic serotonin in the development of the spontaneous (genetic) hypertension in the rat.

5-Hydroxytryptophan↗
PubMed1987

Nuclei of the lateral lemniscus project directly to the thalamic auditory nuclei in the pigeon.

Non-mesencephalic origins of ascending afferents to the thalamic auditory nuclei, nuclei ovoidalis (Ov) and semilunaris parovoidalis (SPO), were identified in the pigeon in retrograde tracing experiments. These origins comprise dorsal and ventral lateral lemniscal nuclei. Injections of anterograde tracers into these nuclei produced terminal labelling in SPO in particular. These experiments show for the first time that the inferior colliculus is not an obligatory relay to the auditory thalamus.

Animals↗
PubMed1992

Afferent innervation of the vestibular nuclei in the chinchilla. II. Description of the vestibular nerve and nuclei.

The morphological characteristics of the vestibular nuclei of the chinchilla were studied in horizontally cut serial sections of the brain stem. Horseradish peroxidase labeling allowed unambiguous delineation of the vestibular nuclei and areas of innervation by the vestibular afferent fibers. The cytoarchitecture of the vestibular nuclei was documented with the aid of camera lucida drawings and quantitatively evaluated with computerized methodology. The cellular groups identified in other species were found in the chinchilla. The superior vestibular nucleus (SN) originated ventromedial to the mesencephalic tract and nuclei of the trigeminal nerve. This nucleus contained medium-sized cells with a central group of larger cells (20-34 microns in diameter). It received its maximum vestibular innervation caudally in the ventrolateral and dorsal aspects of the nucleus. Fibers projected to the SN in bundles with thick fibers surrounded by thin ones. The lateral vestibular nucleus (LN) originated 0.9-1.2 mm below the rostral aspect of the vestibular area. It was ventrocaudal to the SN and contained many large cells with diameters of 45-60 microns. The LN was innervated mainly in the ventrocaudal aspect by oblique and transverse fibers that formed a dense mesh. The medial vestibular nucleus (MN) originated 0.3-0.6 mm caudal to the beginning of the SN, adjacent to the floor of the IVth ventricle. It extended for 3-4 mm along the SN, LN and descending vestibular nucleus (DN). The MN contained the densest and most homogeneous cells, which had diameters of 10-20 microns. This nucleus received its greatest innervation at the level of the vestibular root. Thin fibers traveled to the MN through the SN and LN. The caudal pole of the nucleus did not receive fibers. The DN originated 1.8-2.5 mm caudal to the origination of the SN, between the caudal LN and the MN. Caudally it replaced the LN. Most of the cells of the DVN were medium-sized, with diameters of 10-20 microns. The main vestibular innervation of the DN was in the lateral aspect of the nucleus. Tertiary fibers projected in small, separate bundles of uniform-sized thick fibers. The interstitial nucleus originated 1.1-1.4 mm from the beginning of the SN. It occupied the center of the vestibular root, 0.8-0.9 mm medial to the root entry zone. It contained a few large cells (greater than 20 microns in diameter), many medium-sized cells, and some small cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Afferent Pathways↗
PubMed1976

[Reactions of neurons of the reticular and ventral anterior thalamic nuclei of the cat to electric stimulation of the relay nuclei of the optic thalamus].

Responses of 92 reticular (R) and 105 ventral anterior (VA) thalamic neurons to electrical stimulation of relay nuclei, ventrobasal complex (VB), lateral (GL) and medial (GM) geniculate bodies, were studied in cats immobilized with d-tubocurarine. 72.2% of R and 76.2% of VA investigated neurons responded to VB stimulation, while GM stimulation caused responses only in 15.0% of R and 27.1% of VA neurons and GL stimulation in 10.2% of R and 19.6% of VA neurons. The responses of R-VA neurons to relay nuclei stimulation were expressed, as a rule in excitation. Two types of excited neurons were distinguished: the first group responded to stimulation of afferent inputs by the discharge of 5-15 spikes at a frequency of 250-300 p/s, the second group responded by single action potential. According to peculiarities of their responses, the neurons of the first group are resembling inhibitory interneurons. 2.2% of R and 7.8% of VA neurons responded to relay nuclei stimulation by antidromic spikes. Among R and VA neurons there are cells which respond to stimulation of one, two and even three different relay nuclei. If stimulation of one relay nucleus is followed by a response of R or VA neuron, the preceding stimulation of another relay nucleus, with the time interval between the conditioning and testing stimuli being less than 30-50 ms, induced the inhibition of the response to the testing stimulus.

Animals↗
PubMed1981

RNA metabolism in isolated nuclei: effect of temperature on RNA transport from intact and membrane-denuded nuclei.

The kinetics of RNA transport from intact (both inner and outer nuclear membranes present) and membrane-denuded myeloma nuclei were monitored at temperatures between 10 and 37 degrees C. A linear rate for RNA transport was calculated and the log of RNA transported from membrane-denuded nuclei was greater than that transported from intact nuclei and ii) RNA transport from both nuclear preparations exhibited straight line Arrhenius plots. We conclude the nuclear envelope (or a nuclear matrix element) modulates the amount of RNA transported from nuclei and that nuclear membrane thermal phase transitions do not alter the apparent energy of activation for the transport process.

Animals↗
PubMed1964

THE RELATIONS BETWEEN DNA, RNA, AND PROTEIN IN NORMAL EMBRYONIC CELL NUCLEI AND SPONTANEOUS TUMOUR CELL NUCLEI.

Interferometric and photometric measurements have been made successively on individual cell nuclei derived from normal embryonic tissues and spontaneous tumour tissues of the mouse grown in vivo. From the measurements, the relations between nucleic acid and dry mass content have been studied in the two types of nuclei and the results shown to be consistent with differences in cell metabolism previously reported to exist in vitro. In the nuclei of normal embryonic cells, the syntheses of DNA, nuclear RNA, and protein appear to be closely associated, whereas in the tumour cell nuclei an appreciable fraction of the chromatin RNA and protein synthesis is dissociated from the replication of DNA.

Animals↗
PubMed1978

Estimation of the mean caliper diameter of cell nuclei. I. Serial section reconstriction method and endothelial nuclei from human lung.

In morphometric studies of lung tissue, accurate determination of the total number of any specific type of cell, such as the endothelial cell, requires knowledge of the shape of the cell nucleus. This knowledge of shape is necessary to calculate the mean caliper diameter, which, in turn, is an indispensible element of the equation for the number of nuclei (therefore cells) per unit volume (NV). Nine human hung endothelial cell nuclei were therfore reconstructed in dental wax from serial sections and were found to be pleomorphic triaxial ellipsoids. Five of these approached an oblate shape. The axes of these nine nuclear models were directly measured and a computer program using numerical integration was written to determine the mean caliper diameters of these ellipsoids. The estimated mean semi-axes of the nine nuclei were (+/-SD) 5.98+/-1.61, 3.61+/-0.70, 1.36+/-0.34; and the estimated overall mean caliper diameter for the total population of human lung endothelial nuclei was 7.97+/-1.27 micrometers.

Cell Nucleus↗
PubMed1998

Not only inner cell mass cell nuclei but also trophectoderm nuclei of mouse blastocysts have a developmental totipotency.

The nuclei of mouse trophectoderm cells were found to have developmental totipotency like inner cell mass cells after serial nuclear transfer. Single inner cell mass or trophectoderm cells from expanded blastocysts synchronized with the cell cycle by treatment with nocodazole and aphidicolin to the G1 stage were injected into the perivitelline space of enucleated metaphase II oocytes together with Sendai virus. All oocytes were given three electrical pulses to induce fusion and activation (first nuclear transfer). Aphidicolin was present in all media used until fusion. When reconstituted oocytes developed to the two-cell stage, the nuclei of the reconstituted eggs were fused with the enucleated blastomeres of fertilized two-cell embryos by inactivated Sendai virus (second nuclear transfer). The reconstituted embryos were cultured in vitro and transferred to recipients. After the second nuclear transfer, 23-64% (for inner cell mass cells) and 32-62% (for trophectoderm cells) developed to morula or blastocyst stage. Better development of second nuclear transfer embryos was observed when oocytes fused with trophectoderm nuclei did not extrude a polar body after the first nuclear transfer. After transfer of morulae and blastocysts to recipients, four males were obtained, two from inner cell mass and two from trophectoderm nuclei. These findings indicate that the nucleus of inner cell mass and trophectoderm cells of mouse blastocysts can be reprogrammed within the cytoplasm of unfertilized oocytes and then in fertilized embryos.

Animals↗
PubMed1999

Expression of N-methyl-D-aspartate receptor subunits in the rat parabrachial and Kölliker-Fuse nuclei and in selected pontomedullary brainstem nuclei.

In the present study, we investigated the expression of N-methyl-D-aspartate (NMDA) receptor subunits in the parabrachial/Kölliker-Fuse complex (PB/KF), the intertrigeminal region, the ventrolateral pons, the nucleus of the solitary tract, the ventrolateral medulla with the ambiguus nucleus, and the caudal spinal trigeminal nucleus, which are presumably involved in mediating the autonomic responses to nasotrigeminal stimulation (diving response). Our immunocytochemical data demonstrate that the majority of neurons in the respective nuclei stain for the NR1 subunit, which is a mandatory component of all NMDA receptors. NR1 immunoreactivity was found mainly on neuronal cell bodies and primary dendrites. The ubiquitous expression of the NR1 subunit was confirmed by in situ hybridization, revealing a strong NR1 mRNA signal over neurons in all nuclei investigated. Among the NR2A-D subunits, the strongest expression was observed for the NR2D transcript, both in the PB/KF and in the brainstem. For the PB/KF, we found in addition a moderate expression of NR2A mRNA in the internal lateral PB and of NR2B mRNA in the external lateral PB. The remaining PB nuclei and the KF were essentially devoid of NR2A-C transcripts. For the nucleus of the solitary tract and in the spinal trigeminal nucleus, we found, in addition to the strong NR2D mRNA signal, moderate expression of the NR2A-C transcripts. In the ventrolateral medulla, a moderate signal was seen for NR2C transcript, whereas signals for the NR2A and -B subunits were negligible. Our data suggest that, in PB/KF and pontomedullary brainstem nuclei involved in mediating the diving response, glutamatergic neurotransmission is apparently mediated through a specific type of NMDA receptor channels, consisting essentially of NR1 and NR2D subunits.

Animals↗
PubMed1975

A comparative study of DNA-dependent RNA polymerases from rat ascites hepatoma cell nuclei and from rat liver nuclei.

DNA-dependent RNA polymerases (EC 2.7.7.6) were extracted and partially purified form the nuclei of rat ascites hepatoma cells (AH-130) induced by 4-dimethylaminoazobenzene. The patterns of RNA synthesis and the properties of these enzymes were compared with enzymes from the nuclei of rat liver. The specific activity of RNA polymerase in the homogenate from the nuclei of AH-130 cells was the same as normal rat liver nuclei. RNA polymerase was solubilized from the homogenate at high ionic strength and separated into two forms by DEAE-Sephadex column chromatography. Enzymatic characterization showed that these enzymes corresponded to RNA polymerase I and II. RNA polymerase I more effectively transcribed native DNA than denatured DNA at low salt concentration, but at high salt concentration RNA polymerase I effectively transcribed denatured DNA. RNA polymerase II more effectively transcribed denatured DNA. In AH-130 cells the activity of RNA polymerase I was 4 to 5 times higher than RNA polymerase II, and in rat liver the activity of RNA polymerase I was 1.5 to 2 times higher than RNA polymerase II. The activity of RNA polymerase I in AH-130 cells may have increased by induction.

Ammonium Sulfate↗
PubMed1994

Preparation and characterization of two phosphopeptide fractions from calf thymus nuclei; similarity to corresponding fractions in the DNA prepared from the nuclei.

In this study two phosphopeptide (PP) fractions from purified, calf thymus nuclei, prepared under protective conditions were characterized. The nuclei were lysed and dialyzed, and the material in the dialysates was fractionated by anion exchange column chromatography. This revealed the presence of two main phosphopeptide (PP) fractions, numbers 1 and 5. Amino acid analysis of the fraction 1, occurring in the greatest amount, showed that, after deionization, it contained the metal ion complexes of phosphoserine, aspartic and glutamic acids in large amounts, and nine other amino acids. In the same way the two main PP fractions, P1 and P5, were obtained during the dialysis of the EDTA-reacted, highly purified DNA (N-DNA) prepared from calf thymus nuclei. Fraction 1 from nuclei had practically the same amino acid composition as fraction P1 from EDTA-reacted N-DNA. In both cases, the second main fraction obtained (fraction 5) had nearly the same amino acid composition as fraction 1, but the total Pser molar ratio, was about twice as high as for fraction 1. In contrast to the low molecular weights of 900-1400 daltons observed for PPs isolated directly from the dialysates in water without exposure to HCOOH, the high molecular weight of 10,260 daltons was obtained for the PP fraction 1, after exposure to HCOOH used in the gradient for the column chromatography.

Amino Acids↗
PubMed1987

Responses of neurones in the brainstem raphe nuclei to stimulation of the cerebellar fastigial nuclei in the cat.

Stimulation of the fastigial nuclei of the cerebellum was found to excite units located throughout the raphe nuclei of the brainstem. Raphe spinal units with axons conducting at velocities below 20 m/s were either unaffected by fastigial nucleus stimulation or inconsistently excited at long latency. In contrast units with faster conducting spinal axons throughout the raphe and more dorsally in the reticular formation were excited by stimulation of the fastigial nuclei. Many of these units responded at short latency and followed high rates of repetitive stimulation.

Action Potentials↗
PubMed1987

The projection of the nucleus reticularis tegmenti pontis and adjacent regions of the pontine nuclei to the central cerebellar nuclei in the cat.

The projection of the nucleus reticularis tegmenti pontis (NRTP) and the pontine nuclei (NP) to the central cerebellar nuclei (CCN) was investigated by means of anterograde transport of tritiated leucine. Although termination was found in all the CCN, it was most pronounced in the lateral nucleus and the lateral aspect of the posterior interposed nucleus. The extreme lateral aspect of the anterior interposed nucleus and the caudal part of the fastigial nucleus received a projection of modest intensity. Termination in the infracerebellar nucleus and group Y is likely to be present but could not be confirmed with certainty from the light microscopical material. The contribution from the NP was small and originated from the dorsolateral and dorsal paramedian subdivisions of the NP. Within the NRTP the total area giving rise to projections to the CCN was extensive, and the origin of the projections to the individual CCN overlapped considerably. The projection of the NRTP to the ventrocaudal part of the lateral nucleus was found in conjunction with a projection to the ventrolateral part of the posterior interposed nucleus. Both projections seemed to branch off the fiber bundle terminating in the ventral paraflocculus. Similar correlations could be established in the projection of the NRTP to the dorsal paraflocculus and crus II of the ansiform lobule with other parts of the lateral and posterior interposed nuclei. It was concluded that the transverse, lobular organization of mossy fibers, which differs fundamentally from the longitudinal, modular organization of climbing fibers, is maintained in the collateral projection to the CCN. The results are further discussed in relation to the corticonuclear projection and the engagement of the NRTP and different parts of the CCN in pontocerebellar circuits.

Animals↗
PubMed1993

Branching projections from mesopontine nuclei to the nucleus reticularis and related thalamic nuclei: a double labelling study in the rat.

Branching projections from pedunculopontine and laterodorsal tegmental nuclei to different thalamic targets were studied by means of a double retrograde tracing technique. The results show a topographic distribution of mesopontine neurons projecting to different thalamic targets. In addition, the present data demonstrate that a small percentage (< or = 5%) of mesopontine neurons projecting to the intralaminar nuclei or to the rostral pole of the reticular nucleus innervate both these areas by means of branching axons. By contrast, a large number of mesopontine neurons projecting to the sensorimotor thalamic nuclei send axon collaterals to the caudal part of the reticular nucleus. The present findings support the hypothesis of an inhomogeneity of different sectors of the thalamic reticular nucleus. Thus, this nucleus can be differentiated into two functional areas, in accordance with their connections with functionally different cortical fields and thalamic districts. The possibility that these two areas of the thalamic reticular nucleus subserve different mechanisms during sleep phenomena is discussed.

Animals↗